EhFrameHdr.h revision 37b74a387bb3993387029859c2d9d051c41c724e 
1//===- EhFrameHdr.h -------------------------------------------------------===//
2//
3//                     The MCLinker Project
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9#ifndef MCLD_LD_EHFRAMEHDR_H_
10#define MCLD_LD_EHFRAMEHDR_H_
11#include "mcld/ADT/SizeTraits.h"
12#include "mcld/LD/EhFrame.h"
13#include "mcld/Support/FileOutputBuffer.h"
14
15#include <cassert>
16namespace mcld {
17
18class LDSection;
19class FileOutputBuffer;
20
21/** \class EhFrameHdr
22 *  \brief EhFrameHdr represents .eh_frame_hdr section.
23 *
24 *  @ref lsb core generic 4.1
25 *  .eh_frame_hdr section format
26 *  uint8_t : version
27 *  uint8_t : eh_frame_ptr_enc
28 *  uint8_t : fde_count_enc
29 *  uint8_t : table_enc
30 *  uint32_t : eh_frame_ptr
31 *  uint32_t : fde_count
32 *  __________________________ when fde_count > 0
33 *  <uint32_t, uint32_t>+ : binary search table
34 */
35class EhFrameHdr {
36 public:
37  EhFrameHdr(LDSection& pEhFrameHdr, const LDSection& pEhFrame);
38
39  ~EhFrameHdr();
40
41  /// sizeOutput - base on the fde count to size output
42  void sizeOutput();
43
44  /// emitOutput - write out eh_frame_hdr
45  template <size_t size>
46  void emitOutput(FileOutputBuffer& pOutput) {
47    assert(false && "Call invalid EhFrameHdr::emitOutput");
48  }
49
50 private:
51  /// computePCBegin - return the address of FDE's pc
52  uint32_t computePCBegin(const EhFrame::FDE& pFDE,
53                          const MemoryRegion& pEhFrameRegion);
54
55 private:
56  /// .eh_frame_hdr section
57  LDSection& m_EhFrameHdr;
58
59  /// eh_frame
60  const LDSection& m_EhFrame;
61};
62
63//===----------------------------------------------------------------------===//
64// Template Specification Functions
65//===----------------------------------------------------------------------===//
66/// emitOutput - write out eh_frame_hdr
67template <>
68void EhFrameHdr::emitOutput<32>(FileOutputBuffer& pOutput);
69
70}  // namespace mcld
71
72#endif  // MCLD_LD_EHFRAMEHDR_H_
73